Method of permanently drawing sheet-glass rollers and other hollow articles immediately from the glass-harbor.



W. ZAHRADNIK. METHOD OF PERMANBNTLY. DRAWING SHEET GLASS ROLLERS AND OTHER HOLLOW 7 ARTICLES IMMEDIATELY FROM THE GLASS HARBOR.

APPLICATION FILED DEG. 31, 1912. I

1,085,835. Patented Feb. 3, 1914.:

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METHOD OF PERMANENTLY DRAWING SHEET-GLASS ROLLERS AND OTHER HOLLOW: I

ARTICLES IMMEDIATELY FROM THE GLASS-HARBOR.

To (ZZZ 20710225 it may concern Be it known that I, vVnNzEsLAUs ZAHBAD- win, a subject of the Emperor of Germany, residing at Tschernitz, Niederlausitz, Germany, have invented new and usefullmprovements in Methods for Permanently of molten glass, lifting the bait or drawingtool, then drawing, in ratio to its size, a portion of the glass adhering thereto from the glass bath, whereby, after solidification, the hollow article is formed. After having removed the glass body so formed from the bait or drawing member, the latter is'lowered again into the bath for drawing anew article In connection with one of the known methods, compressed air is supplied from the top, either by a pipe connected with the bait, or by means of a nozzle rising from the glassbath.

lVith a view to avoiding the repeated dipping of the bait into the molten glass for the subsequent hollow articles that are to be drawn, it has been proposed either to retain, by means of a stationary clamping device close to therigid outerwalhthe straight residual section remaining after having disjoined thecylinder made, and subsequently closing said section air-tight by a movable seizing and blasting device and then lifting it: or, according to another suggestion, after disjunction of the drawn cylinder, the straight residual body was gripped with the assistance of an internal cutting device and clamping contrivance, and simultaneously therewith at theouter side. by an outside clamping contrivance, and drawn into a "new hollow article. With all. these known arrangements the great trouble experienced has been that the operator is seldom success"- ful in severing in a horizontal straight line the completed, but still hot, cylinder, it being, however, an indispensable condition for the drawing out of'a new hollow article to close the residual section and to supply and Specification of Letters Patent.

Patented Feb 3, 1914.

Application filed December 31, 1912. Serial No. 739,487.

regulate the blast-air. A section disconnected in an uneven intersection-line cannot be used for continued drawing of hollow articles, by reason of insufficient packing.

In contradistinction to the above, in the presentmethod there is formed a hood-like residual section, by providing the cylinder at the end, where it is lifted out, close to the molten glass, with a recess or restricted portion, and by severin the cylinder above the narrowest point 0 such recess. To provide the cylinder, after the drawing action has been finished, at its bottom end with such a recess, with a view to facilitate its disconnection, is known already; suclrdisconnection did not take place,'howeve'r, under formation of a residual section having a central recess for facilitating the gripping operation; nor has the residual section been made use of for further drawing.

In the present method of operation the gripping and tightening of'the residual section at the mouthpiece below the line of severance is independent of the severance of the drawn cylinder, such severance being elther III a straight or in an untrue line, and

the blast-air can be introduced into the 1101- low glass article to be drawn both from the top and from the bottom. Also the sever- Race; itself is not accom lished at the -nar rowest point, as hereto ore, but above it, with a view to obtaining a broader rim. pro' jecting above the res dual section. This of the residual section in position in the bid opened tongs. The grooved extremity. or restricted portion may either be fully'closed,

characters indicate like parts inthe'several views.

' broader rim is used to facilitate-the holdini'g ,or, 'bysetting in a hollow core, it maybe.

Figure 1 is 'a vertical section of an'apparatus forcarrying out my invention, show-. ing parts in section; Fig. 2 is a plan view, partly in section, of the float.

The melting pot 1 has built close up to it a fore-hearth or tank, 2, for receiving the molten glassfrom thepot 1, which, through an opening 3 flows over from the pot or furnace into the tank 2. In'this fore-hearth 2 there is a floating annular member 4 having in its bottom a nozzle 5 connected by passages 6 and 7 with the compressed air pip ing. The supply through the pipe 8 into the passage 6 can be effected either from the side or from the top. The air supply through the floating annular medium has the advantage that it can follow the variations o'l the level of the molten glass in the fore-hearth.

In order to provide sufficient room forthe alterations of position of the annular memher or float, the fore-hearth 2 is deepened. The pipe section 7 can be tightened at the point of discharge into the passage 6 by glass, which at thetemperature prevailing there remains viscous. The bottom of the float 4 has several apertures through which the molten glass can pass from the forehearth. Through a channel 9 arranged in thepartition between the glass pot or furnace -1 and the fore-hearth 2 the wall is intcnscly cooled, so that the glass in the forehearth 2 gets an even temperature throughout, whereby the mass is kept suitably plastic for drawing the cylinders. The clearance between the float 4 and the walls of the fore-hearth is, of course, kept sufiiciently large, in order to take into account the movements of the glass flowing in, and those of the float.

Into the glass contained in the fore-hearth 2 of the furnace 1 an iron globe-shaped or hell-shaped bait 10 of the known type is dipped just enough so that when it is lifted, the glass remains sticking to its rim; the bait 10 is then slowly raised by means of a suitable device, under constant supply of air through the nozzle 5. The excess of air escapes through the usual aperture 11 in the bait. After having attained a given length, the drawn cylinder isstripped off in the known manner. Th is assisted by the flame of the burner 12.

The drawn cylinder is not severed, as heretofore, at the narrowest part of its lower contracted end at the nozzle 5, but at the normal diameter of the cylinder for forming the "im 1 The cylinder may, however, be severed near the nozzle 5, but above the narrowest point thereof, so that above its most contracted portion there is still a broader rim left for gripping-it. By turnl'ng aside the crane 15 the cylinder is transported to the place of deposition, for being carried alon farther. The farther cylindersare now rawn with the assistance of the residual sections 16. The half-opened lifting tongs 13 are supporting the residual sec- .tion at the point of contraction to prevent it from sinking into the glass-bath, in such a manner that the residualportion 16 with its adhering rim 14 remains in the lifting tongs. Nowthe contracted part may be hermetically sealed, either by compression or by the melted glass; or there may he slipped in from the top into the tapering opening a heated hollow core or support 17, made of metal or of other incombustible material, whereupon, under further heating through the flame of the burner 12, the lifting tongs are closed and firmly pressed toward the core to seal the contracted portion against the core. Now the lifting tongs are raised under simultaneous air supply, and a new cylinder is formed;

Obviously, the compressed air instead of being supplied through a float, may be supplied in a known manner from below through a stationary nozzle, or from the top through the core 17 which has been introduced into the contracted neck. When compressed air .is supplied from below and a core is introduced from the top, the air escapes through the bore in the core 17.

I claim 1. The method of drawing glass cylinders and other hollow articles, which comprises contracting, and gripping the drawn cylinder at the contracted portion, severing the cylinder above the contracted portion and drawing a subsequent cylinder by the residue containing said contracted portion.

52. The method of drawing glass cylinders and other hollow articles, which comprises contracting the lower end of the cylinder, supporting said contracted portion above the surface of the glass from which the cylinder is being drawn, severing the cylinder above the contracted portion, supplying air to the interior of said portion and drawing a subsequent cylinder by said portion.

3. The method of drawing glass cylinders and other hollow articles, which comprises contracting the lower end of the cylinder suflicient for engagement of a drawing tool, severing the cylinder above the contracted portion, closing the contracted portion against a support for maintaining an air conduit through the contracted portion, and drawing a subsequent cylinder.

4. The method of drawing glass cylinders and other hollow bodies, which comprises mechanically contracting the lower end of the cylinder while supplying heat to the point to be contracted, severing the cylinder above the point of contraction, further point to be contracted, severing the cylinder above the point of. contraction, further reducing said contracted portion against a heated hollow support and then drawing a subsequent cylinder by the residue below the point of severance While supplying air to the interiorof the cylinder'being d 'awn.

6. .The method of drawing glass cylinder andother hollowi bodies, which comprises i mechanically contracting the lower end of me cylinder while supplying heat t6 the point t'ofbe cent-meted, severing the cylinder aboi e 'the'point of contraction, further reducing said contracted portion against a I heated-hollow support and then drawing a subsequent cylinder by the residue below the point of severance 'while supplying air through said hollow support to the interior 0f the cylinder being drawn.

In testimony wheref I ,a-fiix hei'eunte ny. 15 signature in the presence-0f two witnesses. 1

Witnesses:

PAUL ARRAS, ARTHUR GUBE.

WENZESLAUS ZAHRADNIK. v

Copies of; this patentmy *be obtained for five cents each, by addressing the Commissioner of Patents, Wash1ngton, 1). CF. 

